Effect on structure and mechanical property of tungsten irradiated by high intensity pulsed ion beam

Highlights: • Cracks and even exfoliation appeared on the surface of tungsten. • The salient points formed on the surface due to the remelting effect when the irradiation times were major. • The micro-nano hardness of the surface of tungsten decreased with the increase of irradiation times and energy densities. The anti-thermal radiation performance of tungsten was investigated by high intensity pulsed ion beam technology. The ion beam was mainly composed of Cⁿ⁺ (70%) and H⁺ (30%) at an acceleration voltage of 250 kV under different energy densities for different number of pulses. GIXRD analysis showed that no obvious phase structural changes occurred on the tungsten, and microstress generated. SEM analysis exhibited that there was no apparent irradiation damage on the surface of tungsten at the low irradiation frequency (3 times and 10 times) and at the low energy density (0.25 J/cm² and 0.7 J/cm²). Cracks appeared on the surface of tungsten after 100-time and 300-time irradiation. Shedding phenomenon even appeared on the surface of tungsten at the energy densities of 1.4 J/cm² and 2.0 J/cm². The surface nano-hardness of tungsten decreased with the increase of the pulse times and the energy density. The tungsten has good anti-thermal radiation properties under certain heat load environment.